Cux1^(+)proliferative basal cells promote epidermal hyperplasia in chronic dry skin disease identified by single-cell RNA transcriptomics

Pathological dry skin is a disturbing and intractable healthcare burden,characterized by epithelial hyperplasia and severe itch.Atopic dermatitis(AD)and psoriasis models with complications of dry skin have been studied using single-cell RNA sequencing(scRNA-seq).However,scRNA-seq analysis of the dry skin mouse model(acetone/ether/water(AEW)-treated model)is still lacking.Here,we used scRNA-seq and in situ hybridization to identify a novel proliferative basal cell(PBC)state that exclusively expresses transcription factor CUT-like homeobox 1(Cux1).Further in vitro study demonstrated that Cux1 is vital for keratinocyte proliferation by regulating a series of cyclin-dependent kinases(CDKs)and cyclins.Clinically,Cux1+PBCs were increased in patients with psoriasis,suggesting that Cux1+PBCs play an important part in epidermal hyperplasia.This study presents a systematic knowledge of the transcriptomic changes in a chronic dry skin mouse model,as well as a potential therapeutic target against dry skin-related dermatoses.

Analysis of a System Describing Proliferative-Quiescent Cell Dynamics

Systems describing the dynamics of proliferative and quiescent cells are commonly used as computational models, for instance for tumor growth and hematopoiesis.Focusing on the very earliest stages of hematopoiesis, stem cells and early progenitors, the authors introduce a new method, based on an energy/Lyapunov functional to analyze the long time behavior of solutions. Compared to existing works, the method in this paper has the advantage that it can be extended to more complex situations. The authors treat a system with space variable and diffusion, and then adapt the energy functional to models with three equations.